The present invention relates to a method of manufacturing a cantilever that measures the atomic force acting between atoms on the surface of a specimen in an atomic force microscope.
U.S. Pat. Nos. 4912822 and 4916002 disclose the conventional structure of a cantilever and the method manufacturing a cantilever 100 .mu.m long and 10 .mu.m wide having a pyramidal needle (6 .mu.m long along the side of the bottom and 7 .mu.m high) made of silicon nitride or tungsten, as shown in FIG. 7, and a cantilever without a needle. That is, the silicon substrate is formed with a pyramidal hole and then coated with a thin film that constitutes a cantilever. By using photolithography, the cantilever is formed into a desired shape, which is put in contact with a glass as a mount.
However, the conventional cantilevers usually do not have a needle or, if they have a needle, the needle at the end of the cantilever is formed in a pyramidal shape with its vertex angle obtuse at 72 degrees. When a measuring portion 26 is to be used to measure deep holes, grooves or high projections on the surface of a specimen 27, as shown in FIG. 7, parts other than the front end of the needle are subjected to atomic force of atoms. In other words, as shown in FIGS. 8B and 8C, the apex of the needle cannot follow the contour of the specimen surface, with the result that the output waveforms cannot reproduce the shape of the specimen surface, as shown in FIGS. 9B and 9C, degrading the resolution.